1,071 research outputs found

    Nanoarchitectonics of metal oxide materials for sustainable technologies and environmental applications

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    Sustainable development compliant with environment and human health protection motivates researchers to explore green solutions towards improved economic and social wellbeing. These objectives, still very far from being achieved especially in developing countries, must necessarily be pursued through the tailored fabrication of low-cost, eco-friendly, efficient and stable multi-functional materials. In particular, nanostructures based on first-row transition metal oxides are amenable candidates for clean energy production, air purification and self-cleaning/anti-fogging purposes, especially if obtained through fabrication strategies allowing a careful modulation of their characteristics. In this highlight, after a brief introduction of the above issues, we provide selected representative examples of green oxide-based nanoarchitectures for the targeted end-uses. Attention is focused on the interplay between the material chemico-physical properties and the resulting functional performances, with the aim of providing some hints to control material behavior by design. In addition, we provide a critical outlook not only on the unique opportunities, but also on the main open challenges related to the use of the above multi-functional materials, in an attempt to stimulate further advancements in these emerging research areas

    Estimating GDP at the Parish (County) Level: An Evaluation of Alternative Approaches (Bulletin #890)

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    Gross Domestic Product or GDP is estimated for each parish from earnings and employment data from more than 60 industries in Louisiana.https://digitalcommons.lsu.edu/agcenter_bulletins/1005/thumbnail.jp

    A multilayer panel in cork and natural phase change materials: thermal and energy analysis

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    This paper presents thermal and energy analysis of a multilayer panel in bio-based cork material and natural phase change materials (PCMs) for the development of prefabricated, recyclable and energy-efficient and autonomous building modules. For this purpose, a calculation tool is developed for the dynamic simulation of the thermal and energy behaviour of the sandwich panel. In particular, through an extensive parametric survey, the panel is sized with the identification of the arrangement of the layers, PCM temperature, and layer thicknesses to optimize the insulating and damping properties, considering typical climatic conditions of the Mediterranean climates of Southern Italy. From the conducted simulations, the types of sandwich panels that have the best insulating and storage characteristics for the building module construction were chosen. The results of these simulations will be used in future research for the preliminary design of tests to be carried out in a climatic chamber and to build a building module in real conditions to be constantly monitored through the automatic instrumental survey of internal and external physical quantities such as temperature, humidity and radiant temperature

    Evaluating the Switch from Cotton to Corn: Impacts on the Louisiana Economy (Bulletin #888)

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    This research measures the net economic impact to the Louisiana economy from a major switch in acreage from cotton to corn in 2007.https://digitalcommons.lsu.edu/agcenter_bulletins/1007/thumbnail.jp

    "Hot" Surface Activation of Molecular Complexes: Insight from Modeling Studies

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    Rock-and-roll over hot floors: Theoretical modeling of the first activation stages of a Cu complex on top of a heated surface (750 K) revealed two mobility regimes, a slow bump-and-rock diffusion over the surface and a fast roll-and-go motion accompanied by significant temperature-induced bond oscillations. This study enables a deeper insight into "hot" surface molecular activation processes.Tanz auf dem Vulkan: Das Modellieren der ersten Aktivierungsstufen eines Cu-Komplexes auf einer beheizten Oberfl\ue4che (750\u2005K) enth\ufcllte zwei Bewegungsarten: eine langsame Diffusion durch \u201eAnsto fen und Taumeln\u201c und eine schnelle Rollbewegung, die mit deutlichen temperaturinduzierten Bindungsoszillationen einhergeht. Diese Befunde geben einen Einblick in die Prozesse bei der Aktivierung durch \u201ehei fe\u201c Oberfl\ue4chen

    Analytical Method for Quantification of Several Phthalate Acid Esters by Gas Chromatography-Mass Spectrometry in Coffee Brew Samples

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    Several phthalate acid esters (PAEs), often called phthalate esters or phthalates, are substances classified as harmful due to their carcinogenic and mutagenic properties, and moreover, as dangerous for humans because they interfere with the endocrine system. In general, phthalic esters are used as plasticizers for different polymers and more other consumer products. In the present study, we describe a simple method to quantify PAEs in coffee brew using a liquid-liquid extraction without purification processes through analysing the obtained organic phase by GCMS in the single ion monitoring mode. The totals of single PAEs, in coffee brew samples analysed by us, are in the range of 159-5305 mu g L-1. Considering that, on average, a person drinks three cups (total 90 mL) of the aforementioned drink per day, this will lead to the uptake of a total 14 to 477 mu g of phthalates

    A Short Review of Simple Analytical Methods for the Evaluation of PAHs and PAEs as Indoor Pollutants in House Dust Samples

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    Studies on indoor air quality are indispensable when considering that people spend approximately 85% of their time in confined environments. This short review mostly takes into consideration research that uses passive samplers to evaluate the quality of indoor environments (houses, school, cars, etc.). This short review summarizes most analytical methods to detect and quantify PAHs and PAEs in house dust used as a passive sampler. The objective of house dust analysis is to identify the presence, amount and distribution of specific hazardous substances in confined spaces and, if possible, to identify their sources. Household dust and the compounds present in it can enter the human body by inhalation, non-food ingestion and absorption through the skin. The observed differences in concentrations of house dust may also indicate important differences in the chemical and physical nature of pollutants caused by air filtration and absorption during the migration of ambient air into the indoor environment

    Determination of Selected Polyaromatic Hydrocarbons by Gas Chromatography-Mass Spectrometry for the Analysis of Wood to Establish the cause of Sinking of an Old Vessel (Scauri wreck) by Fire

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    The aimof this paper was to establish the cause of sinking of an old wooden vessel by polycyclic aromatic hydrocarbon (PAH) analyses because wood combustion is a source of PAHs. In particular, the molecular PAH patterns generated by each source are like fingerprints and it is possible to determine the processes that generate PAHs by studying their distribution in wood samples. The relative abundance of high molecular weight PAHs, together with the PAH compound ratios and with total index (proposed by us) has demonstrated that samples owe their PAHs in wood archaeological material to a predominant single mode of origin, i.e. combustion processes, therefore we can say that the sinking of the vessel was caused by a fire

    Polyphenol characterization and skin-preserving properties of hydroalcoholic flower extract from Himantoglossum robertianum (Orchidaceae)

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    Himantoglossum robertianum (Loisel.) P. Delforge is a Mediterranean orchid whose propagation in vitro has been achieved, making it eligible as a source of bioactive substances. Flowers were analyzed by light and SEM microscopy and used to obtain a polyphenol-rich, hydroalcoholic flower extract (HFE). HFE was characterized for total phenols, flavonoids and proanthocyanidins, and for polyphenol profile by RP-LC-DAD. Antioxidant assays, in vitro collagenase and elastase inhibition, and MTT and cell motility assays on HaCaT keratinocytes were done. Microscopy showed epidermal cells containing anthocyanins in the flower labellum. Flavonoids (flavones and flavan-3-ols) represented the most abundant compounds (42.91%), followed by scopoletin (33.79%), and phenolic acids (23.3%). Antioxidant assays showed strong activities, rating ORAC > FRAP > TEAC > \u3b2-carotene bleaching > DPPH > iron-chelation. Biological assays showed elastase and collagenase inhibition (up to 42% and 78%, respectively), improvement of HaCaT cell viability after treatment with 500 \u3bcM H2O2 (from 30% to 84% of control), and stimulation of cell migration rate up to 210% of control. In summary, HFE counteracted different free radicals, while protective properties were shown by cell-free and cell-based bioassays, suggesting the possible use of H. robertianum flowers for skin-preserving, repair, and anti-aging applications

    Electron transport through single Mn12 molecular magnets

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    We report transport measurements through a single-molecule magnet, the Mn12 derivative [Mn12O12(O2C-C6H4-SAc)16(H2O)4], in a single-molecule transistor geometry. Thiol groups connect the molecule to gold electrodes that are fabricated by electromigration. Striking observations are regions of complete current suppression and excitations of negative differential conductance on the energy scale of the anisotropy barrier of the molecule. Transport calculations, taking into account the high-spin ground state and magnetic excitations of the molecule, reveal a blocking mechanism of the current involving non-degenerate spin multiplets.Comment: Accepted for Phys. Rev. Lett., 5 pages, 4 figure
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